很多同学都能想到用was to来填空,但是后面的时态却都用了attend.有人问为什么要用完成式.因为
, U) t, k/ Y4 b% W, g6 E0 y was (were) + 不定式完成式,这种结构表示“本来打算…,本来要…(而结果则没做)”。) W6 Z7 d6 I0 S6 O4 j: T, P/ b8 K
这个知识点很重要啊,大家可要牢记在心呢.好啦,今天我们要来复习的是have to和must:/ Y% b# ?& _) a9 }1 y% }
have to 和must在表示“必须”这个意思时是很接近的,但也有一定的区别。: _8 u7 @- Z2 j7 B* H2 A4 c5 k
1. have to 比较强调客观需要,表示因客观环境或事态促使而不得不做某事;must强调主观看法,表示主观上认为有必要做某事。例如:! S% W1 [9 Y, a9 e4 ]& \; c
I must learn another language.# C* v% Q% N! Y& g1 b
(主观想法: I want to)7 U% n/ r% H- e* I% Q
I have to learn another language.
6 W+ f& `/ }2 M2 P) G) [ (客观需要:身为一个外交官)2 l& I: L. T O" D/ z
You must be back before 10 o’clock. 2 ?# x( s3 ^+ W9 f' p& T+ `, j
(叮嘱或命令)# Z% K. Q ]% m' \7 n
You have to be back before 10 o’clock because the train is to leave at 10:05.(客观需要)5 _; s! v* p% z% @0 b
2. have to多表示义务或习惯动作;must则用于表示一种重要或急迫的事情。例如: : o3 N0 P: n- y) U$ h3 ]5 Y, U
We have to care for the young.(义务)1 S) C. ]* t$ j5 R
She has to be at the office before eight every day. (习惯), c# s8 j3 ?2 f z8 y& X
You must go to the manager at once, or you’ll be dismissed.
$ B) v+ A4 G+ y2 A* D 务必马上去见经理,不然你会被开除的。(急迫的事情)
: }) v4 p" m' b" K 3. have to可用于不同的时态;而must一般只用于现在时(但也可以表示将来的情况,在间接引语中也可以表示过去时)。例如:9 Y8 c- M" V$ o9 X
I have to (must) leave now.- X" v! J4 s, ~. f4 W0 B
We’ll have to buy another TV set.
+ c2 ?1 S* r/ m) j# ]; m2 B; o2 [ They had to put off the sports meet because of the bad weather.
) g$ N2 N; s7 E# A ] He said that the work must be finished within two weeks./ V& T, J. K# j: F& ?: O
4. must还可以表示一种推断和揣测,而have to则不能。例如:: W) @# f" I2 f/ O
This must be Jin’s pen.
! j; E7 H. ~/ I5 }3 l: a3 G, x7 J s 5. "must+动词完成式"可以用来表示对过去情况的揣测,而have to则不能。例如:6 E. v( P. U% N6 O0 s" `4 t
She must have read the book sometime in the past, or she couldn’t have answered the question so well.
1 T8 |, _7 r3 {* \% a2 |& w 她一定在过去某个时候读过这本书,不然,这个问题她不会回答得这么好的。
; A. k, H" N! ?, C Note:
( v b: k+ s; _7 \# x) b( F 在现代英语中,have to 中不定式和疑问句式既可以按照助动词的变化规则构成,也可以按照行为动词的变化规则构成。例如:& e8 T3 w4 F, s+ N) h- |* l
Have you to finish the work before supper?' J8 C: f0 D, v% X* ^4 I* A: i, E
Do you have to finish the work before supper?
9 I( a4 Y! N, y' S" a: e have got to 常可同have to换用,但有时表示不同的含义。比较:
' ?7 @* A m1 t+ D1 } He has to report to the headquarters every two days.(例行公事,习惯动作)
0 @/ A6 O1 M" e* \ He has got to report to the headquarters every two days.(一道指示或命令,必得每天报告一次)8 G) B2 Y O# D& c9 P9 A3 d
另外,作“有”解时,have got和have通常是可以换用的,have got更口语化,但有时表示不同的含义。比较:
2 o* z7 Z K- \" X. a The man has a blind eye.那人有一只眼瞎了。
! M/ B; n9 e8 G The man has got a blue eye.那人有一只眼被打青了。
+ h* O2 O1 U+ w- H$ }, J must not表示禁止,是说话人强有力的劝告或命令,意为“一定要,不准”。因此,在回答由must引导的问题时,如果是否定的回答,表示“不必,没有必要”,不能用mustn’t,而要用needn’t或don’t have to.试比较:5 Q$ V/ m0 ?6 U1 h0 e; F
You must not drive fast.你不能开快车。(路险或有速度限制)
5 o" G) q, t: ~. ?9 I! o5 y6 B6 [ You needn’t drive fast.(时间充裕) |